This is Steven Salzberg's blog on genomics, pseudoscience, medical breakthroughs, higher education, and other topics, including skepticism about unscientific medical practices. Here's where I can say what I really think about abuses and distortions of science, wherever I see them.

One of this summer’s biggest hits was the movie Jurassic World, which earned a record $209 million on its opening weekend back in June. It's so popular that it’s still showing in theaters now, more than two months later.

Like its predecessors, the fourth movie in the Jurassic Park series features a theme park filled with dinosaurs that were created by cloning dinosaur DNA. In the movie, the dino DNA was collected from mosquitos preserved in amber, which (in the fictional movie world) had sucked the blood of dinosaurs 65 million years ago.

The success of the movie spurred YouGov.com to conduct a poll, asking Americans if they believed it was currently possible to create dinosaurs from DNA found in fossils. 28% said yes.

It makes for a fun story, but is there any science behind it? Well, yes and no.

Can we clone a living organism entirely from scratch, just from its DNA sequence alone? Yes! Not only can we do it, but it has already been done. Genome scientists Craig Venter and Hamilton Smith, both former colleagues of mine, achieved this at least twice, creating bacteria by synthesizing the necessary DNA and then “booting up” a new bacterial cell, which went on to replicate itself and grow into colonies of brand-new bacteria. Very impressive work, although bacterial genomes are quite small, only a few million nucleotides long.

Moving up a step, just last year, Hopkins scientist Jef Boeke (who is now at NYU) and his team synthesized an entire yeast chromosome. Yeast are single-celled like bacteria, but they're eukaryotes, evolutionarily closer to humans and dinosaurs than bacteria. Eukaryotes keep their DNA sequestered inside a nucleus, which in turn makes them way harder to clone from scratch. Synthesis of the remaining yeast chromosomes is under way, and it’s entirely feasible that we’ll have artificial yeast in just a year or two.

As of today, though, no one has even come close to synthesizing a multi-cellular creature like a dinosaur–or a chicken, or a frog, or a human. But in principal, it is possible to create a living animal just from its DNA, though it might take a few more decades to do it.

So yes, we might someday create animals from DNA. But dinosaurs? Alas, this half of the Jurassic World question gets a big “no.”

The problem is, despite the compelling story in the movie, there is no dinosaur DNA left on the planet. None at all, despite what you might have read. Dinosaurs went extinct about 65 million years ago, mostly likely because of a massive asteroid impact in the Yucatan peninsula, and DNA simply doesn’t last that long.

But wait, you might ask: what about all these stories about Neandertal DNA, or woolly mammoth DNA, or other ancient species? These studies are true and are very exciting. Scientists have reconstructed the genome of our Neanderal relatives from very old bones, around 30,000-40,000 years old. We can extract DNA from bones that old, although the DNA is badly degraded. I worked on an ancient DNA project myself, using an 11,000 year old mammoth thigh bone to reconstruct part of its genome. We were able to recover quite a lot of mammoth DNA from that bone.

Other work on ancient samples has demonstrated that in the most extreme conditions, where the bones have been continuously frozen in the Greenland ice sheet, DNA may survive as long as 1 million years. However, dinosaurs lived in temperate climates where DNA degrades far more quickly, and virtually all dinosaur DNA was probably gone within a few thousand years after the dinosaurs became extinct.

(By the way, that same YouGov poll that asked about cloning dinosaurs also asked "Do you believe that dinosaurs and humans once lived on the planet at the same time?" 40% of Americans said yes, demonstrating once again that Americans are woefully misinformed about evolution and the history of the planet.)

So alas, a mosquito that sucked the blood of a Tyrannosaurus rex, and then got swallowed and preserved in tree sap, would not yield any T. rex DNA for present-day cloning experiments.

This doesn’t mean we’ll never have a Jurassic Park, but if we do, we’ll have to guess at what that dino DNA looked like, perhaps using the DNA of birds. Perhaps, though, we should focus on saving the species we have left, which we are rapidly wiping out, before worrying about reviving long-lost dinosaurs.

Just two months ago I wrote about Wisconsin Governor Scott Walker's dual attacks on his state's flagship university. Walker, who is currently running for the Republican nomination for President, is moving to eliminate tenure for professors at the University of Wisconsin, while at the same time implementing an enormous $250 million budget cut.

This week we learned a new reason why Gov. Walker cut that $250 million: he wants to give it to wealthy hedge fund managers to build a new basketball arena for the Milwaukee Bucks.

No kidding. I can only imagine what my colleagues at the University of Wisconsin are thinking.

On Wednesday, Walker signed a bill that would spend $250 million of taxpayers' money to build the new arena. Last year, the team was purchased by two billionaire hedge fund managers, Marc Lasry and Wesley Edens. In what's become a standard ploy, the new owners threatened to move the team if they didn't get a new arena.

The libertarian Cato Institute denounced the public financing of the arena, according to the New York Times. Other Republicans are furious with Walker because one of the team's co-owners (Lasry) is a major supporter of Hillary Clinton's campaign.

When I wrote about Walker's attacks on the University of Wisconsin in June, I was mystified by why he would go on the offensive against an institution that his state should be incredibly proud of–and that provides countless benefits to the state and the nation. It seemed petty and vindictive, and it still does.

But the money cut from the University of Wisconsin, $250 million, exactly matches the state's contribution to the new arena for the billionaire hedge fund owners of the Milwaukee Bucks. It's now obvious what Scott Walker's priorities are.

Birth control pills have been around since the 1960s, when they offered women a revolutionary degree of control over their reproductive capabilities. Over the years, the formulation of "the pill" has changed, but it remains one of the most widely used, and most effective, forms of pregnancy prevention.

This week, a very large new study in The Lancet Oncology reported that use of birth control pills provides a significant, and surprisingly large, reduction in the risk of endometrial cancer. The benefit lasts for decades–women who used the pill in the 1960s have the same reduction in cancer rates as women who took it more recently. This is very good news for women.

The new study combined data from 36 earlier studies covering a total of 27,276 women with endometrial cancer and 115,743 without it. The authors–a large group called the Collaborative Group on Epidemiological Studies on Endometrial Cancer–have been working for ten years to collect and analyze this massive data set. Overall, they found that the risk of endometrial cancer in women who had used the pill was only 69% of the risk in women who had never used it. The benefit increased with longer usage: for every 5 years on the pill, women had a 24% reduction in the relative risk of cancer.

Relative risk of endometrial cancer (red line) based on how many years a woman used birth control pills. From "Endometrial cancer and oral contraceptives: an individual participant meta-analysis of 27,276 women with endometrial cancer from 36 epidemiological studies", published online 4 August 2015 in The Lancet Oncology.

Endometrial cancer is the most common gynelogical cancer, accounting for 6% of all cancers in women. The National Cancer Institute estimates that in the U.S., 54,870 women will be diagnosed with endometrial cancer in 2015, and 10,170 will die.

To put the benefit of birth control pills in numeric terms, the new study reports that:

"In high-income countries, 10 years use of oral contraceptives was estimated to reduce the absolute risk of endometrial cancer arising before age 75 years from 2.3 to 1.3 per 100 women."

The benefit is even larger for women who used the pill longer: after 15 years the risk of cancer drops to 1%. The authors estimate that over the past 50 years, the pill has prevented 400,000 endometrial cancers in western Europe, the U.S., and Australasia, including 200,000 in the past decade.

The policy implications of this new study are profound, and likely to be controversial. Women have long struggled to control their reproductive rights, and in many countries access to the pill is still very limited. Even in the U.S. the fight for access to birth control continues: just last year, the Supreme Court ruled in favor of a private corporation, Hobby Lobby, that claimed it had religious objections to providing birth control as part of its health care coverage. (Never mind the absurdity of the notion that a corporation could claim to have religious views.)

Now there's a new and very different reason to provide birth control pills as part of health care coverage. Time will tell whether this dramatic cancer prevention benefit will trump the objections of those who want to deny women access to the pill.